1. Field of the Invention
This invention relates to Die-Casting Machines, and more particularly to Tie-Bar Style Die-Casting Machines. The invention provides a die-space access system for use with the tie-bar style die-casting machine. The system provides improved access to the die space of the machine for the removal and/or installation of dies.
2. Background Information
Die casting machines and die casting processes have been used for many years to produce metal castings for a variety of applications in a variety of industries, such as in the manufacture of automobile transmission housings and drive train components. Castings are produced by supplying molten metal, such as aluminum, magnesium and alloys thereof, under pressure to a die. A die is installed and positioned in a die casting machine, closed and locked. Subsequently, the molten metal is delivered to a cold or hot piston pump and driven though a feeding system to the cavities of the die. Pressure is applied for a predetermined time to allow the casting to solidify. The die is then opened and the casting is ejected. This process is typically repeated though multiple casting cycles until the die is removed for cleaning or replacement.
Tie-bar style die casting machines, which utilize tie-bar pullers to secure a die in the die space of the machine are well known in the art. A plurality of threaded tie bars permit opening and closing of the die halves between casting cycles. Existing tie-bar systems have significant limitations and shortcomings. Most significantly, they do not provide ease of access to the die space for installation and removal of dies therefrom. Ease of access to the die space allows for fast die changes and resultant efficient use of energy, manpower and material in die casting operations. Other problems exist with respect to adjustment of tie bar tension, and even and consistent closing of the die, for example. Prior art tie bar machines require frequent individual manual adjustment of the tie bars during operation. Such adjustments procedures also result in inefficiencies in operation.
U.S. Pat. No. 4,285,384 to Wunder discloses an apparatus and method for tie bar nut drive system. This apparatus and method are for removing tie bars from a die casting machine to permit removal and insertion of dies. The apparatus and method involve utilizing gearing attached to the tie bar nut whereby the nut is held captive, but is capable of being rotated by an auxiliary drive unit. The locking nut is rotated to a preselected position and locked.
Despite the need in the art for a die space access system for use with tie-bar style die casting machines, and which overcomes the shortcomings and limitations of the prior art, none insofar as is known has been developed or proposed. Accordingly, it is an object of the present invention to provide a die space access system for use with a tie bar style die casting machine which permits improved installation and removal of dies. Another object of this invention is to provide a die space access system which permits accurate and reproducible adjustment of tie bar tension. It is a further object of this invention to provide a die space access system which is reliable, durable, simple to manufacture and use, and which overcomes the general limitations and shortcomings of the prior art.